Sometimes the images appear to be blank. This is usually caused by: (a) there are only a small number of objects in the picture that are visible at the selected exposure time (e.g., only Pluto, Charon, and a couple of fairly bright stars are visible in 1x1 mode LORRI images when the exposure time is less than 150 ms), and/or (b) the intensity stretch is not optimized for the limited dynamic range of the signal in the image. In either case, you might want to download the JPEG yourself (the full version, not the thumbnail) and play with the intensity stretch using image processing software on your computer (on an Apple computer, you can use either the Preview or iPhoto applications; there are similar options on other computers). For example, you might start seeing objects if you move the white level of the stretch to smaller values. And you may need to magnify particular regions to see the object(s) better. See what you can find by digging a bit deeper!